Preheat oven to 350F.

Bring a large pot of water to boil. Peel the sweet potatoes and cut in to large cubes. Boil until sweet potatoes are cooked through. Drain and return to pot.

Add vegan butter, non-dairy milk, brown sugar, vanilla extract, cinnamon, nutmeg, ginger, and salt. Mash with a potato masher until smooth. Spread sweet potato mash in to a casserole dish. I used an 11"x7" baking dish. Set aside. 

Next, make the pecan topping. Cream together the softened vegan butter and brown sugar in a small bowl. Add in the flour, chopped pecans, vanilla, and cinnamon. Mix well. Sprinkle the pecan topping over the sweet potato mixture.

If making day of, bake the casserole for 45 minutes.

If making tomorrow, cover and refrigerate. 

When the casserole is done baking, set it aside to cool. 

In a stand mixer, add the aquafaba and the cream of tartar. Beat on high until firm peaks form, about 6-7 minutes. 

In a small pan over medium heat add the coconut oil and marshmallows. Mix until starting to soften. Then, add the non-dairy milk and whisk until completely melted. Carefully add the melted marshmallow to the aquafaba and keep whipping the mixture. Then, add in the powdered sugar and vanilla extract. The meringue is done when everything is incorporated and the mixture is light and fluffy. Should take about 10-15 minutes from start to finish. 

Once the casserole is slightly cool, spread the marshmallow meringue evenly on top by using a spatula or get fancy and use a piping bag. You probably won't need all of it. Use leftovers as a whip cream on top of your Thanksgiving pie! Set oven to broil. Broil until meringue is slightly golden brown.